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Luke Kuechly, Andrew Luck headline the Audibles All Second-Year Team

Luke Kuechly has been an anchor for the Panthers' second-ranked defense. (Gary Bogdon/SI)

It's hard to know what to make of second-year NFL players. For every rookie disappointment who sees the light, there's a first-year star who falls into a sophomore slump. Now that we've seen enough of these players at the midway point of Season 2, here are our picks for the league's most talented second-year men.

2013 has certainly been an interesting season for those first-year stars from 2012 -- were we to take current peak value into effect, we might say that Nick Foles and Case Keenum are the best sophomore signal-callers in the NFL. But we'll give this to Luck, because he's managed to be highly effective in two entirely different offenses, from Bruce Arians' downfield attack in his rookie campaign to Pep Hamilton's more conservative approach now. He's done it with a highly inconsistent offensive line, one receiver he can count on in Reggie Wayne (who is now out for the remainder of the season) and a variable rushing attack. Wilson gets our backup vote because he's been able to extract wins from an offense with questionable protection at best.

Running Backs -- Alfred Morris, Washington Redskins

Honorable Mention: Doug Martin, Tampa Bay Buccaneers

Morris is our lead-pipe lock here -- he led all rookies with 1,613 rushing yards in 2012, and he's far and away the best among second-year backs with 686. Were it not for his shoulder injury, Martin might be ahead of him this season; he had 456 yards in six games. How hard is it for second-year backs to excel this season? Miami's Lamar Miller is third with 448 yards, and after that, it's two quarterbacks -- Wilson and Robert Griffin III -- who round out the top five in rushing yards this season.

Hilton could stand to catch a few more of the passes Luck throws his way, but as he proved in Sunday night's three-touchdown performance, there are few current NFL players more dangerous as a pure vertical threat. Jones put up four touchdowns against the Jets on Oct. 27, but he's no one-game wonder -- he has seven touchdowns this year, and he currently ranks first in Football Outsiders' per-play metrics among qualifying receivers. Gordon would be first on this list if he had a less cluttered personal history, but his talent is undeniable.

It's tough to argue against Colts GM Ryan Grigson as having the best overall haul in the 2012 draft -- Luck was a gimme as the first overall pick, but to get Hilton, Allen, Fleener and the currently-injured Vick Ballard in the same class? That's pretty darned impressive. It was Allen who impressed last season, but when he went down with a hip injury, Fleener started to hit the scene in 2013.

The 2012 draft was a mixed bag for offensive linemen. Kalil has probably been the best overall from the class, but you'd expect that given his fourth-overall selection. The Lions took Reiff with the 23rd pick in the first round, and he's developed pretty well despite some physical limitations.

Pittsburgh Steelers guard David DeCastro, the offensive lineman I liked the most from that draft, missed his entire rookie year and is getting the hang of things at this point. Zeitler has been an anchor on perhaps the league's best overall line in 2013, and Osemele (who was a tackle at Iowa State and moved to guard in 2013) performed reasonably well for Baltimore on the inside until back injuries ended his season. Konz moved from guard to center (the position he played at Wisconsin) in his second season, and while he's not a world-beater just yet, he's the best we've got.

Outside of the quarterback position, this might prove to be the best group from the 2012 draft when we look back 10 years from now. Poe is a candidate for Defensive Player of the Year after a rocky first year, and Brockers has been destroying guards and centers for the Rams' estimable front seven.

We're cheating a bit with Cox, who's played inside and outside and is currently an end in Billy Davis' 3-4 defense, but he's got three sacks, seven QB hits and 30 hurries from that position. He also amassed four sacks as a tackle in whatever the heck the Eagles were doing on defense in 2012. Jones was the second most prolific rookie sack artist behind Seattle's Bruce Irvin last season, and he's already got 8.5 takedowns this season.

Irvin clogs up our OLB list because he moved there from defensive end for the 2013 season. He's still getting the hang of that position, but he's developing in his dropbacks into coverage, and he has as much pure speed as any edge rusher in the league. David is the sure-fire winner at this position, and one of the best young players in the NFL. Trevathan may be known primarily to the general football-watching populace for a couple of boneheaded plays, but he's got three picks and eight passes defenses to go along with a sack and some quality run defense. Not bad for a sixth-rounder in 2012.

You could make the argument that Kuechly is the most impactful player on this list -- when he's on, he's nearly unstoppable. He's the best of the league's new wave of 360-degree linebackers -- just as adept in coverage as he is running opponents down in space. Wagner has been a stalwart for Seattle's outstanding defense, and Freeman is a sneaky impact player who went undrafted out of the University of Mary Hardin-Baylor, which we had never heard of before he started to make an impact.

There's little doubt that Jenkins would have been a first-round pick had he been able to stay out of trouble, and the Rams managed to turn that trouble into a relative steal with the 39th overall selection. Jenkins isn't totally refined with his technique, but he's one of the more effective press corners in the NFL at a time when the league requires more physical pass defenders. Hayward has played left and right corner, but he's been most effective in the slot as a key cog in Dom Capers' defense.

Barron's still getting the hang of coverage, but he brings additional value in the box at linebacker depth. Like most Alabama defensive backs who were taught by Nick Saban, he'll need time to adapt to the complexities of the backpedal -- Saban likes his guys to run up to coverage or stick to a man. Smith had a fine rookie season and was looking forward to more before turf toe robbed him of a follow-up year. Ihenacho came out of nowhere as an undrafted free agent, blowing the Broncos away in the 2013 preseason after spending his rookie year alternating between the active roster and practice squad. So far, the 2012 draft has been rough at this position.